A conventional structure of a roof rack is generally made up of a plurality of longitudinal bar and a plurality of transverse bars. The longitudinal bars are respectively mounted to and extending along opposite sides of a car roof. The transverse bars extend between and are fixed to the longitudinal bars on the two sides of the car roof. The combined arrangement of the longitudinal bars and transverse bars allows a roof box, luggage tray, luggage carrier, a bicycle rack, a kayak holder, a snowboard rack, or a ski rack to be positioned on the car roof.
Taiwan Utility Model M267119 discloses a locking structure of a roof rack structure, wherein a coupling base and a coupling board are both provided with clamping sections. The clamping section of the coupling base has a top portion in which a channel is formed. The channel functions to receive and retain a transverse bar. Formed under the channel is an insertion slot for receiving an insertion tab of the coupling board to be fit therein. A bolt is screwed through the coupling board and coupling base to allow them to be attached to a longitudinal bar by means of the clamping sections. A top end of the clamping section of the coupling board is arranged to form the insertion tab, while a bottom end comprises a threaded hole formed therein to receive the bolt to extend therethrough, whereby when the clamping sections are used to couple to the longitudinal bar, the bolt is set through and coupling base and is screwed to the coupling board to have the coupling base and the coupling board attached to the longitudinal bar. An end of the transverse bar is fit into the channel of the coupling base. Screws are then put through the coupling seat to screw into the transverse bar to have the transverse bar fixed to the longitudinal bar.
Such a known structure of a roof rack has the following disadvantages:
(1) The assembling is complicated. Bolts and screws that are different must be respectively applied to secure the longitudinal bar and the transverse bar. Such an assembling operation requires a great number of different bolts/screws to complete securing and fixing. In addition, a detaching operation is thus also complicated.
(2) The assembling or detaching operation is extremely time-consuming. Due to the complicated process of assembling, a great amount of time is necessary for attaching or detaching.
Thus, the present invention aims to provide a structure of a roof rack, which can effectively reduce the amount of time necessary for assembling and detaching and can achieve easy attaching and detaching of a roof transverse bar to a roof longitudinal bar through rotation of the bars.